The technology described herein relates to a method of and an apparatus for generating an output frame. In particular, the technology described herein relates to a method of and an apparatus for generating from an input frame an output frame to be displayed on a display device or to be written to memory.
When an image is generated, for example to be displayed on a display device, the image generally requires processing before being displayed. The processing may for example include scaling with respect to the dimensions of the display, upscaling of a low resolution image to a higher resolution image or vice versa, applying a sharpening or smoothing algorithm to the image, performing image enhancement or composing the image with other data such as text or another image, generating information (metadata) about the image, etc.
In a conventional display device, such image processing is generally performed at the frame refresh rate of the display, for example at 60 fps. For currently available tablet display devices, e.g. with a resolution of 2048×1536 pixels at 32bppx, to refresh the display at 60 fps requires the processing of 720 MB of data per second.
Image processing is normally performed in a “single pass”, in that the processed image is sent directly to the display without being written to memory. It may be performed within the display controller of the display device or by a processing engine that is separate from the display controller. Performing image processing in a single pass is conventionally considered advantageous as the processed images are used immediately instead of being written back to memory, which would have increased the requirement for bandwidth and power.
However, as display resolutions continue to increase and image processing performed in mobile devices become increasingly complex in order to improve image quality, image processing is expected to become more computationally expensive.
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